I've discovered is that all I really need to get the tone I want is a closed back. I can only get the C50 so close to the wall, and anyway I'd like to gig again some day, so I'm wondering about using something to change it from open to closed. It's the 2x12 combo, with the standard Blue Marvel speakers. Disclaimer - I am NOT good with woodworking, and have no tools, so I need something simple...though I may be able to enlist the help of a neighbor that is a woodworker. Any idea if the speakers in this would be OK with a closed back? Other things I should consider? Thanks!